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> 先化简再求值:x2-1x+1-x2+2x+1x2+x÷1x+1,其中x=-2.-数学
先化简再求值:x2-1x+1-x2+2x+1x2+x÷1x+1,其中x=-2.-数学
题目简介
先化简再求值:x2-1x+1-x2+2x+1x2+x÷1x+1,其中x=-2.-数学
题目详情
先化简再求值:
x
2
-1
x+1
-
x
2
+2x+1
x
2
+x
÷
1
x
+1
,其中x=-2.
题型:解答题
难度:中档
来源:巴中
答案
原式=
x-1-
(x+1)
2
x+1
+1
若x>-1,则原式=x-1;
若x<-1,则原式=x+1;
故当x=-2时,原式=-1.
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化简:(2xx-1-xx+1)÷xx2-1.-数学
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题目简介
先化简再求值:x2-1x+1-x2+2x+1x2+x÷1x+1,其中x=-2.-数学
题目详情
答案
若x>-1,则原式=x-1;
若x<-1,则原式=x+1;
故当x=-2时,原式=-1.